Slough: the centre of the heat pump revolution

Just a thirty minute journey from Paddington on the recently-opened Elizabeth Line takes you to Slough, home to a giant R&D warehouse that’s shaping the future of heating. 

Inside the warehouse lies two full-size buildings, built to represent around 40% of UK homes. These buildings are fully fitted-out with carpets, furniture and gas boilers – but no full time occupants. Instead, they act as a training centre for people that want to learn how to install air source heat pumps (ASHPs). 

Transitioning away from heating buildings with gas boilers and towards low-carbon solutions such as heat pumps is critical to protecting the environment. Homes currently account for 16% of total greenhouse gas emissions and approximately 35% of total energy consumption in the UK. Natural gas is the most common heating fuel in domestic buildings: there are currently approximately 22 million households in the UK with gas boilers, and 1.7 million gas and oil boilers are replaced or installed annually. 

To combat domestic heating emissions the UK government has stated its ambition to install 600,000 heat pumps per year by 2028. This sits in contrast to the UK Climate Change Committee’s assessment that in order to reach net zero by 2050, we should be aiming for 900,000 heat pumps per year by 2028. Yet currently, fewer than 30,000 heat pumps are being installed annually. Octopus Energy wants this to change and is committed to offering customers heat pumps powered by low-carbon electricity, at a competitive price. To do this, they’re building a workforce equipped with the skills required to scale-up the installation of heat pumps. 

Training a workforce fit for the future 

Most people who arrive at this training centre come with relevant, previous expertise. As Lisa who manages the facility told Centre for Net Zero when we visited recently, the hands-on interview involves installing a radiator. The centre welcomes many plumbers, electricians, and former gas boilers and engineers looking to retrain, the process of which currently takes about two weeks. It involves everything from safely disconnecting gas boilers to fitting wall wiring and different types of heat pumps. To install a heat pump system, it takes around five days and involves a team of four to five people. 

In total, Octopus aims to train around 1,000 engineers per year at the centre, and this number is set to rise following the recent acquisition of an additional warehouse. As more engineers are trained and installations are scaled up, the overall cost for a heat pump will fall. It’s currently the biggest adoption barrier, costing between £6,000 – £16,000 versus approximately £2,500 for a gas boiler. Octopus is seeking to bring this down to £5,500 within the next year. 

Market innovation vs government intervention 

The UK government recognises the need to fuel heat pump adoption in the near-term and encourage the market to mature. It announced a Boiler Upgrade Scheme (BUS) in March this year, offering a £5,000 grant to help people overcome the upfront cost of installing the technology. But is this sufficient if we’re to meet our 2028 goals?

Centre for Net Zero undertook a detailed, simulation-based assessment of existing and new interventions required to meet the heat pump target. It showed that whilst the Boiler Upgrade Scheme will result in an uptick in installations during its lifetime, this will fall to pre-grant levels immediately as it ends. Of the scenarios modelled, only interventions including an early boiler ban, announced by 2025, generate enough uptake of heat pumps to reach the Government 2028 target. 

Importantly, our modelling showed that the pool of trained heat pump installers is key. We found that interventions could grow demand for heat pumps to the necessary level, only to be constrained by an insufficient number of heat pump installers. To hit Government targets, as many as 30,000 heat pump installers may be needed by 2028. Whilst this is a tenfold increase on the estimated 2,800 heat pump installers active today, but only about a quarter of the total number of gas boiler installers.

What’s next for the heat pump training centre? 

As we walked around the warehouse, we saw trainees expanding their skills beyond heat pump installations, learning how to install solar panels on roofs and fit home electric vehicle (EV) chargers. It’s clear that the centre is trying to equip trainees with the growing diversity of skills required to fully retrofit households and roll out low carbon technologies. With the opening of a second warehouse and a more specialised R&D function on the horizon, Slough looks set to continue spearheading the future of green heating in the UK. 

Quickfire Q&A

What is a heat pump and how do they work?

‘A fridge in reverse’, heat pumps take heat from the air or ground, raises its temperature enough to turn it into gas, compresses the gas and increases its temperature, then transfers heat to water for central heating and hot water taps. 

How long does it take to install one?

From an initial customer enquiry to installation, it takes about four – six weeks. Actual installation takes roughly five days. 

How much does it cost? 

Depending on the size of the building, an ASHP costs between £6,000 – £16,000. The Boiler Upgrade Scheme offers a grant of £5,000 and costs are expected to fall in relative terms as the market matures.

How efficient are they?

For every 1kWh of electricity used, heat pumps generate up to 4kWh of heat in return. Rather than using short sharp bursts of extreme heat to warm your home, they run radiators at slightly lower temperatures but for a little longer, heating a building to the same temperatures as a gas boiler, but in a far more efficient way. 

Are heat pumps a new technology?

No – they’ve been around for over 100 years and are used widely by people in Northern European countries. They are particularly popular in Norway, where one in every four people own a heat pump. 

How do running costs compare with gas boilers?

New analysis shows that as a result of the recent increases in gas prices, households can now save up to 27% on their heating bills by fitting an efficient heat pump compared to a gas boiler. With the Government looking to shift green levies from electricity to gas, heat pumps could become even more financially attractive. Furthermore, by opting for a smart tariff, consumers can save £250 a year versus a typical gas boiler.